Cover Crop: A Definition

Using Cover Crops on a Small Farm

Rye cover crop, Portage La Prairie, Manitoba, Canada.
Mike Grandmaison/All Canada Photos/Getty Images

A cover crop is a type of plant grown primarily to suppress weeds, manage soil erosion, help build and improve soil fertility and quality, and control diseases and pests. Cover crops are usually grasses or legumes but may be comprised of other green plants.

Cover Crop Benefits

Cover crops improve biodiversity by increasing the variety of species in a given area. They also can help reduce the amount of water that drains off a field, protecting waterways and downstream ecosystems from erosion.

And because each root creates pores in the soil, they help allow water to filter deep into the ground. As a result, they help conserve water in several ways.

Cover crops can help break disease cycles by reducing the amount of bacterial and fungal diseases in a soil. If you have a soil that is infested, you can plant a cover crop in that area and see if you can eradicate the disease.

They are also called "green manure" and "living mulches" because they provide nutrients to the soil much like manure does. And they are called "living mulches," as they can prevent soil erosion.

Organic Gardening with Cover Crops

Cover crops are an important part of sustainable agriculture because they add fertility to the soil without chemical fertilizers via biological nitrogen fixation. They are also a natural way to reduce soil compaction, manage soil moisture, reduce overall energy use, and provide additional forage for livestock.

Small farmers choose to grow specific cover crops based on their needs and goals and the overall requirements of the land they are working.

Cover crops grown in summer are often used to fill in space during crop rotations, help amend soil, or suppress weed (living mulch). Winter cover crops help hold soil in place over the winter and provide ground cover.

They can fix nitrogen levels at the same time.

Once the crop is fully grown or the farmer wants to plant in a given area, he will usually mow down the cover crop and allow it to dry. After it's dry, the remaining organic matter is usually tilled into the soil.

Farmers have to wait a few weeks after tilling before planting the site where the cover crop was with vegetables or flowers.

Cover Crop Examples

Here are some examples of cover crops:

  • Rye: Also known as winter rye or cereal rye, this cover crop might be chosen to loosen compact soil and suppress weeds.
  • Buckwheat: Fast-growing buckwheat helps prevent erosion and suppress weeds.
  • Clover: Clover is great at fixing nitrogen in the soil, adding fertility.
  • Sorghum: This hybrid cover crop grows quickly, adds biomass and suppresses weeds.
  • Hairy Vetch: Vetch adds nitrogen and is a good overwinter crop for northern climates.

Get more in-depth information about each of these and why you might choose each one for your small farm.

Learn more about how to use cover crops on your small farm.